- Sat Apr 16, 2022 3:55 pm
#94312
array81 wrote:I have a WEMOS D1 mini. I need use it with a battery (I have a WEMOS battery shield for this). I'd like check battery state by voltage measurement however I have a problem.
I need use A0 pin with humidity sensor, so I cannot use ADC_MODE(ADC_VCC) because in this way A0 doesn't work any more.
Is therea way to get both voltage and use A0 pin?
I agree with Bonzo on the internal one's accuracy. I've seen boards hooked up to the
same USB port range in voltage readings between about 2.9 and 3.6V. Each one is stable for
that board, just it seems to have drastically different set points.
Another alternative instead of getting an A/D would be get a different humidity sensor. I've used DHT11 and DHT22's in a class and the students have a lot of troubles with them. I've recently started using AHT10's and so far they seem to be more consistent, accurate and cheaper. In lots of 10, they're $1.70 a piece. Don't recall how much for singles. Here's what I teach with in class now with the AHT10 -
https://InqOnThat.com/InqWeatherI think, if I had to choose, I'd keep the voltage checking on the ADC_MODE. Once you load your Sketch and use your volt meter to get the voltage, you could use some multiplication factor in the Sketch and know your ADC_MODE reading would match your volt meter reading.
If you use the ESP's A0 for your humidity sensor, you'll have to find a way to calibrate it and calibrating humidity is far from trivial.
Good luck.
